%单位抽样序列
function [x,n] = impseq(n0,n1,n2)
    if ((n0<n1)||(n0>n2)||(n1>n2))
        error('参数必须满足n1<=n0<=n2');
    end
    n = n1:n2;
    % x=[zeros(1,(n0-n1)),1,zeros(1,(n2-n0))];
    x = (n-n0)==0;
end

